My ESX lab, parts listed below all purchased from NewEgg:
Item List
MEM 2GX2|A-DATA ADQVE1B16K R - Retail (Qty=2, Price=$139.98)
MB JETWAY JM26GT3-SVP AM2 - Retail (Qty=2, Price=$79.98)
CASE LINKWD|313G-C2628 BK/SIL % - OEM (Qty=2, Price=$55.98)
CPU AMD|A64 X2 4000+ 2.1G AM2 65N R - Retail (Qty=2, Price=$111.98)
FLASH 1G|KST FLDRV DTI/1GBKR R - Retail (Qty=2, Price=$11.98)
Extended Warranty Fee: 0
Subtotal: 399.90
TAX: 0.00
Shipping and Handling Charge**: 44.71
Total: 444.61 Not bad for a 2 node ESX cluster.
Plopped in old Intel 10/100 PCI cards that I had collecting dust in each, ESX 3i installable onto the USB thumb drives, Solaris 10 w/ZFS for ISCSI target, another old solaris box for NFS datastore... The MB supports up to 4 x 2GB RAM, so can grow from 4 GB to 8GB in each server. Also plan on getting a cheap gigabit switch and a few gig NICS. very functional, especially for studying for VCP exam.